1. Field of the Invention
The present invention generally relates to networking. More specifically, the present invention provides techniques and mechanisms for improved measurement of network diagnostic metrics.
2. Description of Related Art
There are a number of available metrics that can be used to roughly diagnose the health of a network. Latency is one metric that can be affected by a wide array of problems in the network including congestion, route flaps, non-optimal forwarding topologies, etc. However, because of the difficulty in synchronizing the clocks on two different network devices with sufficient precision, measuring one-way latency is typically not very useful.
Round trip time (RTT) is a commonly used networking metric for determining congestion between a source and a destination in a variety of networks. Networking tools and utilities allow a source to send data to a destination and the destination to respond to the source. The measured time between transmission of the data and receipt of the acknowledgment is referred to as the RTT. The RTT can be used by the source to estimate network congestion and latency between a source and a destination.
The RTT can also be used to set transmission rates at a source. For example, if the RTT is relatively small, a source may interpret it as an indication of reduced network congestion and elect a higher transmission rate.
Current mechanisms for determining network metrics such as latency and RTT have significant limitations. Consequently, it is desirable to provide techniques for improving the measurement of network metrics such as latency and RTT.